diffraction gratingdiffraction grating
See also interferometer
diffraction grating - Computer Definition
An optical device comprising a set of fine parallel slits or grooves etched onto a material in order to product interference patterns that separate components of a spectrum of incoming light. The fundamental principle is that different wavelengths diffract to different extents, so they can be separated much as a prism separates a composite polychromatic incident light beam into its constituent wavelengths of light. Human beings see this as the separation of white light into a rainbow of colored light. There are two types of diffraction gratings:
A device that breaks up an electromagnetic wave into its different frequencies (wavelengths) by scattering them at different angles. For example, a series of thousands of scored lines in a glass plate diffracts light into a rainbow of colors. Lines of data pits on a CD give the same effect. See diffraction.